webhook/node_modules/eslint-plugin-import/docs/rules/first.md
2020-08-26 09:57:08 +10:00

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# import/first
This rule reports any imports that come after non-import
statements.
## Rule Details
```js
import foo from './foo'
// some module-level initializer
initWith(foo)
import bar from './bar' // <- reported
```
Providing `absolute-first` as an option will report any absolute imports (i.e.
packages) that come after any relative imports:
```js
import foo from 'foo'
import bar from './bar'
import * as _ from 'lodash' // <- reported
```
If you really want import type ordering, check out [`import/order`].
Notably, `import`s are hoisted, which means the imported modules will be evaluated
before any of the statements interspersed between them. Keeping all `import`s together
at the top of the file may prevent surprises resulting from this part of the spec.
### On directives
Directives are allowed as long as they occur strictly before any `import` declarations,
as follows:
```js
'use super-mega-strict'
import { suchFoo } from 'lame-fake-module-name' // no report here
```
A directive in this case is assumed to be a single statement that contains only
a literal string-valued expression.
`'use strict'` would be a good example, except that [modules are always in strict
mode](http://www.ecma-international.org/ecma-262/6.0/#sec-strict-mode-code) so it would be surprising to see a `'use strict'` sharing a file with `import`s and
`export`s.
Given that, see [#255] for the reasoning.
### With Fixer
This rule contains a fixer to reorder in-body import to top, the following criteria applied:
1. Never re-order relative to each other, even if `absolute-first` is set.
2. If an import creates an identifier, and that identifier is referenced at module level *before* the import itself, that won't be re-ordered.
## When Not To Use It
If you don't mind imports being sprinkled throughout, you may not want to
enable this rule.
## Further Reading
- [`import/order`]: a major step up from `absolute-first`
- Issue [#255]
[`import/order`]: ./order.md
[#255]: https://github.com/benmosher/eslint-plugin-import/issues/255